A wide variety of multiplate clutch mechanisms are known. Such mechanisms typically require a substantial throw to accommodate for wear and the like. Furthermore, such clutches typically require manual adjustment to accommodate for wear and the like. One such clutch is illustrated in FIG. 1.
The clutch of FIG. 1 is shown to be associated with the output shaft 1 of an engine. Power from the output shaft 1 is transmitted to a driven shaft 4 by means of a centrifugal clutch 2 and a controlled clutch 3. The centrifugal clutch 2 serves to transmit power from the output shaft to the controlled clutch 3 only when the speed of the engine exceeds a predetermined level. The controlled clutch 3 is controlled by a clutch lever 6 to alternately engage and disengage the clutch plates for changing gears and the like. Looking in some greater detail to the clutch of FIG. 1, the controlled clutch 3 is brought into a disengaged condition by actuating the clutch lever 6 angularly in a predetermined direction. An axially movable portion 7A of a clutch cam mechanism 7 is advanced toward the left, as seen in FIG. 1, through the action of cam balls 7B operating between the axially movable portion 7A and an axially nonmovable portion 7C. By moving the portion 7A to the left, a lifter body 8 operating as a clutch release member which is engaged with the movable portion 7A also moves to further drive to the left a clutch lifter 9, a bearing 10 and a pin 11. The movement of the pin 11 results in actuation of a pressure plate 12 which is also moved toward the left in FIG. 1 against the bias force of a clutch spring 13. The movement of the pressure plate 12 releases the pressure exerted between the pressure plate 12 and a clutch center 14 on clutch plates 15 and clutch discs 16. Through release of the pressure, the clutch 3 becomes disengaged.
To engage the clutch 3, clutch lever 6 is released so that it may move angularly to return to its initial position. This allows the axially movable portion 7A of the clutch cam to also return along with the intermediate elements to bring the pressure plate 12 back into position compressing the clutch plates 15 and discs 16 against the clutch center 14 under the influence of the clutch spring 13. The axially movable portion 7A is also returned under the influence of a spring 17 under compression between the axially movable portion 7A and the clutch lifter 9.
To accommodate for wear and thermal expansion of the materials on the faces of the clutch discs 16, this type of clutch provides a manually operative adjuster means 7D mounted to the exterior of the clutch housing. When sufficient wear, for example, occurs, the clutch no longer is completely engaged when the clutch lever 6 is fully released. Consequently, the adjuster 7D is employed to loosen a nut 7E for adjustment of the base 7F upon which the lifter body 8 is slidably positioned.